The war against the Locust Horde is on the not-so-distant horizon according to Chris Morgan, screenwriter for the "Gears of War" game-to-film adaptation. Morgan revealed to MTV News that the movie is now in the budgeting phase. While funds are lining up for the project, casting has yet to begin for the lead role of Marcus Fenix, a disgruntled ex-convict who takes up arms as a member of the human military's crack Delta Squad.

"Normally when I write, I think about the actor I'm writing for, but this one's been difficult," Morgan admitted when asked about casting Fenix in the film. "It is a vital casting choice. It's counter-intuitive really, because it seems like you want to get a big character -- a big tough guy who can play it stoic the whole time -- but in my experience, dealing with macho sorts of movies and dealing with Dom [Vin Diesel's character in "Fast & Furious"] and that kind of stuff, it's harder to play the tough guy than an emotional character who's all over the place."

The short answer, Morgan says, is finding "a really f'ing good actor to pull off being a silent tough guy and put some humanity into it." So who does Morgan think could possibly ride that fine line between dangerous brute and emotional introvert?

"The Rock is awesome," Morgan said of wrestler-turned-actor Dwayne Johnson. "There's a genuine actor. Not only can he play the tough guy, but he can also play the nuanced, sensitive funny sad moments as well. But finding that guy is incredibly difficult."

While Johnson could easily embody the larger-than-life physique of Marcus Fenix, Morgan maintains that the size of the actor is less important than his dramatic chops.

"I don't think they're looking so much for size, but a guy you believe can throw a punch, and a guy you believe is stoic, locked in his own head, and [can] show emotion without telegraphing it," said Morgan. "If you just play the big tough guy, it comes off as one-note and cardboard and not a believable character. So an actor has to find little things and put emotion into them that works in a more subtle way than just being stoic."

Do you think Dwayne "The Rock" Johnson would be a good choice for Marcus Fenix? Should the studio go with a lesser-known actor for the role? Give us your casting suggestions in the comments!